Liquid or pasty product ice cube maker

ABSTRACT

The invention concerns a method and an equipment for making ice cubes of liquid or pasty products comprising a honeycomb conveyor belt transporting the product to be processed along a path passing through at least the following three zones: a zone for metering and depositing the product to be processed in the cells; a cold input zone where preferably a cryogenic liquid solution completes the freezing of the ice cubes; and a stripping zone. Further, the honeycomb belt is bottomless, and located in an upstream zone opposite a cooled surface acting as a base of the partial mold formed by the cells, so as to harden the part of the product in contact with the cooled surface, thereby producing the base of the ice cube.

The present invention relates to the field of methods and installationsfor the cryogenic treatment of products, in particular food products,and more particularly methods and installations for producing “icecubes” or “pellets” or “tablets” from liquid or pasty products. Mentionmay be made in this category of examples of ice cubes from sauce, puree,juice or other liquids.

In recent years, methods have been seen to appear that employ, in orderto produce such ice cubes, tunnels with honeycomb belts, thus consistingof an articulated chain of small molds that are filled with the mixtureto be frozen, the stripping of which molds makes it possible to obtainice cubes with the desired shape and characteristics.

This category of methods is found in document EP-1 115 637.

One of the well-known problems for these production methods is theadhesion of the tablets to the belt or support used, and thereforestripping difficulties, giving rise to material loss, surface marking ofthe tablets etc.

Document EP-1 115 637 provides, for its part, a special honeycomb beltstructure facilitating stripping and limiting material losses. Itprovides precooling of the belt by dipping in a bath of cryogenic liquidbefore the liquid to be treated is poured into the honeycomb cells,which makes it possible for them to obtain crusting of the outersurfaces of the tablets, and the products are then stripped andtransferred to a more conventional deep freezer in order to completedeep freezing the tablets to the core.

It is therefore one of the objectives of the present invention toprovide a novel method for producing frozen tablets or ice cubes makingit possible not only to solve problems of adhesion and material loss,but also to provide a more simple solution that can be incorporatedwithin a single item of equipment.

As will be seen in greater detail below, the method for producing icecubes from liquid or pasty products according to the invention ischaracterized by the employment of the following arrangements:

-   -   employing a bottomless honeycomb belt, conveyed in the equipment        along a path passing through various zones of the equipment;    -   metering and depositing the fluid to be treated (sauce, juice        etc.) in the cells of the belt in an upstream zone of the        equipment;    -   the belt is located in this deposition zone opposite a cooled        surface (for example a metal plate of a cryogenic fluid        exchanger) that serves as a bottom for the partial mold made up        of the cells. In this first zone, the part of the liquid in        contact with the cooled surface is cooled or crusted so as to a        certain degree to create the bottom of the ice cube;    -   thereafter, the belt continues its path in the equipment to        bring the “pre-crusted” ice cubes into a zone where cooling is        provided, making it possible to achieve freezing of the ice        cubes, completely or partly, but preferably freezing to the core        (it will be understood that according to the intended        applications downstream, it is not always necessary to have        core-freezing available), provision of cooling by any means even        though it is preferred according to the invention to achieve        this provision of cooling by causing the belt to pass through        (be immersed in) a bath of cryogenic liquid, to a height        preferably at least equal to the height of the bed of product in        the molds.

For reasons that will be given in greater detail below, other methodsfor providing cooling can be envisaged according to the applications(mechanical cooling, sprays, porous belt of the type of that of documentEP-A-505 222 etc.) but they are not preferred according to the presentinvention for reasons of productivity (it is necessary to run fast) butalso in order to limit the risk of blowing away the fluid, for examplethe sauce.

-   -   The belt then leaves the zone where cooling is provided, for        example the zone where there is immersion in a bath, in order to        reach a zone where stripping occurs, for example due to the fact        that, on leaving the equipment, the belt is rolled up around a        shaft fitted with positive impressions that not only drive the        belt but that can also be forced into the orifices of the belt        (since it is bottomless) in order to push the ice cubes out of        the molds.

The present invention therefore relates to an item of equipment forproducing ice cubes from liquid or pasty products, comprising ahoneycomb conveyor belt capable of conveying the product to be treatedin the equipment along a treatment path passing through various zones ofthe equipment, and employing the following measures:

-   -   the equipment comprises successively at least the following        three zones:    -   i) an upstream zone comprising a device for metering and        depositing the product to be treated in the cells of the belt;    -   j) a zone for providing cooling;    -   k) a stripping zone.    -   said conveyor belt is a bottomless honeycomb belt;    -   the belt is located in said upstream zone opposite a cooled        surface that acts as a bottom for the partial mold made up of        the cells.

In preferred embodiments of the invention, it is additionally possibleto make use of one and/or another of the following arrangements:

-   -   said cooled surface is a metal plate of a cryogenic liquid        exchanger;    -   said zone for providing cooling is a bath of cryogenic liquid        into which the belt passes on leaving said upstream zone, the        height of the bath being preferably at least equal to the height        of the bed of product in the cells;    -   said zone for providing cooling comprises one or more processes        for providing cooling among the following processes: mechanical        cooling, sprays of cryogenic liquid, a porous belt that can be        impregnated with cryogenic liquid;    -   the stripping zone comprises a shaft fitted with positive        impressions around which the belt is rolled up, that not only        drive the belt but can also be forced into the cells of the belt        in order to push the ice cubes out of these cells.

The invention also relates to a method for producing ice cubes fromliquid or pasty products, in an item of equipment comprising a honeycombconveyor belt capable of conveying the product to be treated in theequipment along a treatment path passing through various zones of theequipment, the equipment comprising at least the following three zones:

-   -   i) an upstream zone comprising a device for metering and        depositing the product to be treated in the cells of the belt;    -   j) a zone for providing cooling;    -   k) a stripping zone,        the method employing the following measures:    -   said conveyor belt is a bottomless honeycomb belt;    -   the belt is located in the zone upstream from where the product        to be treated is deposited, opposite a cooled surface that        serves as a bottom for the partial mold made up of the cells, so        as to produce crusting of the part of the product in contact        with the cooled surface and to create in this way the bottom of        the ice cube;    -   complete or partial freezing of the ice cubes is carried out in        the zone for providing cooling.

Preferably, the ice cubes are frozen to the core in the zone forproviding cooling.

According to one of the embodiments of the method according to theinvention, the ice cubes are frozen in the zone for providing cooling bycausing the belt to pass through a bath of cryogenic liquid, of whichthe height is preferably at least equal to the height of the bed ofproduct in the cells.

Other features and advantages will become apparent from the followingdescription, given solely by way of example and made with reference tothe appended figures in which:

FIG. 1 is a diagrammatic representation in section of an installationfor generating ice cubes according to the invention;

FIG. 2 makes it possible to visualize better an embodiment of the“bottomless” honeycomb belt.

The present invention has the advantage of being used in a single andcomplete item of equipment, that ranges from the formation of ice cubesto their freezing and stripping.

It is traversed from one end to the other by a honeycomb conveyor belt,but with the important point that the belt, and therefore the cells, isbottomless (as can be seen perfectly in FIG. 2 that shows an example forthe production of such a belt suitable for implementing the invention).

In an upstream zone, the belt encounters a device for metering anddepositing the product (for example a sauce) to be treated in the cellsof the belt. According to the invention, the belt is situated in thisupstream zone opposite a cooled surface (here a liquid nitrogen contactexchanger) that serves as a bottom for the partial mold made up of thecells.

It has been understood in the light of the preceding description thatthis first zone makes it possible to cool/crust the portion of productin contact with the cooled zone and therefore to a certain degree tocreate the bottom of the ice cube, which will facilitate subsequentstripping.

Indeed, on leaving this upstream zone, the belt leaves the contact withthe cooled surface and reaches a zone for providing cooling, here a zonefor immersion in a bath of liquid nitrogen, a bath of which the heightis preferably at least equal to the thickness of the bed of sauce in thecells, in order to obtain freezing of the pre-crusted ice cubes to thecore.

As has been already mentioned above, other methods for providing coolingcan be used, complementary to, or as a replacement for, the cryogenicbath in the zone for providing cooling, according in particular to thesubsequent application for which such ice cubes are intended (FIG. 1illustrates for example the additional presence of fans and cryogenicfluid sprays) but it has already been noted that these methods are notpreferred according to the present invention for reasons of productivity(it is necessary to run fast) but also in order to limit the risk ofblowing away the sauce by the action of such fans or sprays.

The belt then leaves the zone for providing cooling in order to reach astripping zone, which for the embodiment shown here is constituted bythe fact that on leaving the equipment the belt is rolled up around ashaft fitted with positive impressions that not only drive the belt butcan also be forced into the orifices of the belt (since it isbottomless) in order to push the ice cubes out of the honeycomb molds.

Although the production of square ice cubes has been described as anexample in the preceding description, it will be understood that thecells of the belt could adopt any other form, and in particular acylindrical, rectangular or even fantasy form, for example in the formof small figures.

1-7. (canceled)
 8. An item of equipment for producing ice cubes fromliquid or pasty products, comprising a honeycomb conveyor belt capableof conveying the product to be treated in the equipment along atreatment path passing through various zones of the equipment, andemploying the following arrangements: a) the equipment comprisessuccessively at least the following three zones: 1) an upstream zonecomprising a device for metering and depositing the product to betreated in the cells of the belt; 2) a zone for providing cooling; and3) a stripping zone; b) said conveyor belt is a bottomless honeycombbelt; and c) the belt is located in said upstream zone opposite a cooledsurface that acts as a bottom for the partial mold made up of the cells.9. The item of equipment for producing ice cubes of claim 8, whereinsaid cooled surface is a metal plate of a cryogenic liquid exchanger.10. The item of equipment for producing ice cubes of claim 8, whereinsaid zone for providing cooling is a bath of cryogenic liquid into whichthe belt passes on leaving said upstream zone, the height of the bathbeing preferably at least equal to the height of the bed of product inthe cells.
 11. The item of equipment for producing ice cubes of claim 8,wherein said zone for providing cooling comprises one or more processesfor providing cooling among the following processes: mechanical cooling,sprays of cryogenic liquid, a porous belt that can be impregnated withcryogenic liquid.
 12. The item of equipment for producing ice cubes ofclaim 8, wherein the stripping zone comprises a shaft fitted withpositive impressions around which the belt is rolled up, that can inthis way not only drive the belt but can also be forced into the cellsof the belt in order to push the ice cubes out of these cells.
 13. Amethod for producing ice cubes from liquid or pasty products, in an itemof equipment comprising a honeycomb conveyor belt capable of conveyingthe product to be treated in the equipment along a treatment pathpassing through various zones of the equipment, the equipment comprisingat least the following three zones: a) an upstream zone comprising adevice for metering and depositing the product to be treated in thecells of the belt; b) a zone for providing cooling; and c) a strippingzone, and employing the following measures: d) said conveyor belt is abottomless honeycomb belt; e) the belt is located in the zone upstreamfrom where the product to be treated is deposited, opposite a cooledsurface that serves as a bottom for the partial mold made up of thecells, so as to produce crusting of the part of the product in contactwith the cooled surface and to create in this way the bottom of the icecube; and f) complete or partial freezing of the ice cubes is carriedout in the zone for providing cooling.
 14. The method for producing icecubes of claim 13, wherein the ice cubes are frozen in the zone forproviding cooling by causing the belt to pass through a bath ofcryogenic liquid, of which the height is preferably at least equal tothe height of the bed of product in the cells.